The number of buildings with large glass or flat facades is increasing all over the world. These facades must be periodically cleaned using manual cleaning which is the conventional method today to clean external surface of high rising building.
Cleaning windows on high rise buildings is both difficult and expensive. Workers utilize the Building Maintenance Unit (BMU) to reach the facade. While the cradle of BMU is moving in front of building's windows, cleaning workers occupying the cradle use sponge and cleaning detergent to wipe clean the facade. This procedure has high risk for the workers and takes weeks to clean the facades of a single high rise structure. The workers sometimes have to perform their work under intense conditions leading risking injury. The method is also messy in operation and is highly sensitive to the weather condition. After cleaning one high rise structure the workers need to move to other side of the building with the equipment making it a laborious and time consuming process.
Apart from the high cost and time for cleaning, another disadvantage of current method is that windows can only be cleaned in longer intervals, and it is not cost effective to wash individual sections of the building even if the need persists. Also as the facade workers are not always a part of Building Maintenance, important information could be seen or leaked during the cleaning process.
Though a few automated or semi-automatic applications exist for cleaning buildings in the market, but have failed due to reasons like; a weak safety concept, poor cleaning quality, requiring additional construction to the facade, expensive initial or operating costs, unable to avoid obstacles such as an open window or minor structural protrusion. Even though some methods have been successful to some extent but are applicable only to a particular building.
Accordingly, a need exists for a window cleaning system that can be operated autonomously and which can be utilized for performing overall periodic cleaning or performing cleaning on an as needed basis. The present invention overcomes the weaknesses of existing systems by simple designing of the machine to clean wide range of high rise building of glass or flat facades.